Electric installation



M. SCHENKEL.

ELECTRIC INSTALLATION.

APPLICATION FILED DEC.'4, 1920.

1,433,155 Patented 0@t.24,1922.

i Patented Oct. 24, 1922.

UNITED STATES 1,433,155 PATENT OFFICE.

Mom rz soHENKEL, on CHARLOTTENBUBG, ennmanmnssmnon To. SIEMENS- scnu'oxnnrwnnxn GESELLSCHAFT MIT'BESGHRANKTER 'HAFTUNG, or smmnnss'rnn'r, NEAR BERLIN', GERMANY, A GERMAN CORPORATION.

ELECTRIC INSTALLATION. Application filed December 4, 1920. Serial No. 428,424.

To azll'whm'n it may concern:

Be it known that I, MoRrrz SCHENKEL, a citizen of the German Empire, residing at Charlottenburg, Germany, have invented 6 certain new and useful Improvements in.

'ElectriceInstallations (for which I have filed application for patent in the following countries: Germany, November 15, 1915, Ser. No. 44599; Sweden, January 7, 1920, Ser: NoL89/20; England, April 21, 1920, No.'.142,116; Austria, February 18, 1920,

Pat. No. 88,605; France, March 12, 1920, i Pat. No. 511,496; Switzerland, February 10,

1920, Pat. No. 90,166), of which the follow- .ing is a specification.

This invention relates to arrangements and connections of circuits, which are fed from a source of current having a pulsating voltage and in which the pulsations are substantially equalized in one or more work circuits in such a manner that the current in these circuits pulsates onlyslightly, con-- stituti ng in the most favorable case a pure direct current. Such arrangements are necessary for instance in direct current circuits, which are fed from an alternating source of current by way of valve apparatus (vacuum rectifie'rs) because these devices, unless operated at a largenumber of phases furnish pulsating direct current. The sub ect matter of the present invention is, however, in-

sertion of self-induction in the work cir-- cuit and by the arrangement of ohmic resistances in the shunt circuit. However, (these arrangements are effective only when the work circuits to which the shunt is con- -nected, do not contain any voltage generators such as for instance, storage batteries, generators or motors, all of which generate independently E; M. F.s i..e. electro-motive forces, the'direotions and values of which are independentot the circuit supplying current to the work circuit.

In order to render the current uniform in circuits containing such individual, independent volta'ge generators, above mentioned. according to the invention, a shunt is formed for the alternating current component of the pulsating continuous current, by causing the alternating current component of the pulsating voltage to pass through a circuit connected inparallel with the consuming apparatus through the intermediary of a transformer, the said shunt circuit containing the secondary winding of the transformer. This secondary winding is connected in series with a continuous current generator, the voltage of which, varies at the same rate as the voltage of the current consuming apparatus in the work circuit, this generator] being adjusted so that only asmuch continuous current can flow through this circuit-as is required for themaintenance of its working, for instance, for the driving the voltage generator or forthe overcoming ohmic resistances.

Two arrangements for carrying the invention into effect are diagrammatically illustrated in Figures 1 and 2 of the accom panying drawings. It is assumed in both modifications, as an eXaInple,-that the pulsating direct current is supplied through a vacuum valve, e. g. a mercury vapor rectifier 1. The anodes a of this rectifier are connected in known manner to the secondary winding of an alternating current transformer 2, which is connected to an alternating current supply circuit 3.

Referring more particularly to Figure 1, from the middle of the secondary transformer winding and from the cathode 0, the conductors 4 and 5 respectively lead in the conventional manner to the work circuit, in which the current is to be rendered substantially uniform. This work circuit contains a direct current motor 6,-having a shunt winding 7.

'lVhen the direct current motor 6 is in operation, an E. M. F. is generated at its brushes, whose value is variable independently of'the E. M. F in the supply circuit.

In order to prevent the alternating cur-' rent pulsations from affecting this working sistance circuit, a transformer 12 is provided, whose winding 8 .is located in the main circuit,

connected by way of fieldrheostat 18 in parallel to motor. 6. It is the purpose of this controllable auxiliary machine 13 to generate adirect current potential of the same direction as that of the utility motor 6, and variable in the same sense.

, Now if pulsating direct current flows through transformer winding 8, its alternating cur rent component is transferred into winding 9. Thus the current, due to this component is forced to" flow through the branch circuit, containing winding 9 and the auxiliary generator. vent a direct current of substantial inten sity from flowing through this branch or shunt circuit, acounter E; M. F. is generated in auxiliary generator 13, whichprevents-the flowing of such direct current. On the other hand, care should be taken that the self-induction of this auxiliary shunt circuit otherwise is small compared with -that of the Work circuit, so that in this shunt circuit no substantial inductive reinay oppose the alternating component of the pulsating current. It is therefore advisable to provide auxiliary generator 13 with compensating windings.

The object of the transformer winding 9 is to provide a shunt path for the alter nating current part of the total current so as to relieve the work circuit of the alternating current component of the pulsating former windin 9 is made smaller in itself by co-acting with the second transformer winding 8 carrying the total pulsating cur rent. in place of the impedance 9 an ohmic resistance may be used; the total impedance of the braich circuit can also be formed by the auxiliary machine 13.'

In the modification shown in Figure 2, a direct current shunt motor 13 serves for providing the counter electromotive force, which prevents the passing of the direct current into the shunt circuit by which the In order to prealternating current component is shunted around the Work circuit. The shunt winding 17 of this motor is supplied with current from the work circuit branch which is free from pulsations. In this modification, a direct current flows in the shunt circuit only of a value, suflicient to run motor 13 at no-load. The speed of this motor always regulates itself automatically in such a manner that,-disregarding the drop in the -no-load voltage, the'counter E. M. F. appearing. at its brushes always becomes equal to the continuous current voltage attheterminals of-the work circuit.

The impedances'ofthe circuits can be adstance as shown at 19.

justed by means of choking coils, for in- In Figure 2 a further modification ac cording to the invention is shown, namely -a direct current auxiliary winding 20. coupled with the transformer 12. This winding isfed from a direct current machine 21 driven from the shaft of the shunt motor 13 and the current is controlled by way of a regulator 22 and a choking coil'24. This winding 20 has the purpose of neutra-lizing wholly or partially the direct current field of the transformer produced in the windings 8 and 9. A strong direct current field would impair the transformer in its character asan' alternating current conveyor, The choking coil 24 is intended to smoothen out or suppress the alternating current component induced in the circuit of the winding 20 by the transformer alternating field. In order to make the direct current intensity in the winding 20 dependent on the work current intensity, the machine 21 is provided with a compensating winding 23, in series with motor 6.

While the modifications shown and described contain dynamo electric machines in the shunt and work circuits, the arrangement, according to this invention, is also suitablefor using any other kind of po ten'tial producers, such for instance as storage batteries or the like.

I claim I 1. llna circuit arrangement of the character described, having a source of pulsatingdirect current and a Work circuit containing a generator of potentials independ ent of that of the pulsating current, a circuit arranged in shunt to said work circuit and a transformer for causing the component alternating current of said pulsating current to pass through said shunt circuit,

the primary winding of said. transformer being located in the pulsating current supply circuit, the secondary winding being located in said shunt circuit, and an independent auxiliary source of direct current potential'located in said shunt circuit and means for controlling said source by the potential generator in said work circuit, to

vary the auxiliary potential in accordance direct current and a work circuit containing a generator of potentials independent of that of the pulsating current, a circuit arranged in shunt to said work circuit and a transformer for causing the component a'lternating current of said pulsating current to pass through said shunt circuit, the primary winding of said transformer being located in the pulsating current supply circuit, the secondary winding being located in said'shunt circuit, and an independent auxiliary source of direct current potential located in said shunt circuit and means for controlling said source by the potential generator in said work circuit, to vary the auxiliary potential inaccordance with the potential in the work circuit, and an impedance connected into said shunt circuit in series with said auxiliary potential source.

3. In a circuit arrangement of the cha'racter described, having a source of pulsating direct current and a work circuit containing'a generator of potentials independent of that of the pulsating current, a circuit arranged in shunt to said work circuit and a transformer for causing the component alternating current of said pulsating current to pass through said shunt circuit, the primary winding of said transformer being located in the pulsating current supply circuit, the secondary winding being located in said shunt circuit, and an auxiliary direct current dynamo-electric machine located in said shunt circuit and having its field winding connected in parallel to the potential generator in said Work circuit, to

cause the variation of the auxiliary'machine potential in accordance with that of the work circuit.

4. In a circuitarrangement of the character described, having a source of pulsating direct current and a work circuit containing a generator of potentials independent of that of the pulsating current, a circuit arranged in shunt to said work circuit and a transformer for causing the component al-' ternating current of said pulsating current to pass through said shunt circuit, the primary winding of said transformer being located in the pulsating current supply circuit, the secondary winding-being located-in said shunt circuit, an auxiliary direct cur rent dynamo-electric machine located in said shunt circuit and having its field Winding connected in parallel to the potential generator in said work circuit, to cause the variation of the auxiliary machine potential in accordance with that of the work circuit,

and demagnetizing means, controlled by the current in said work circuit for eliminating the direct current field insaid transformer.

5. In a circuit arrangement of the character described, having a'source of pulsating direct current and a work circuit contaming a generator of potentials independent of that of the pulsating current, a circuit arranged in shunt to said work circuit and a transformer for causing the component alternating current of said pulsating current to pass through said shunt circuit, the primary winding of said transformer being located in the pulsating current supply circuit, the secondary winding bein located in said shunt circuit, an auxiliary direct ourrent dynamo electric machine located in said shunt circuit and having its field Winding connected in parallel to the potential generator in said work circuit, to cause the variation of the auxiliary machine potential in 

